Sulfonamides in diffusion transfer systems

ABSTRACT

POSITIVE IMAGES OF INCREASED MAXIMUM DENSITY IN DIF FUSION TRANSFER SYSTEMS ARE PRODUCED BY PROCESSING THE EXPOSED PHOTOGRAPHIC ELEMENT IN THE PRESENCE OF WATER-SOLUBLE NON-SILVER HALIDE REDUCING SULFONAMIDES. THE SULFONAMIDES ARE PREFERABLY UTILIZED IN ALKALINE PROCESSING COMPOSITIONS COMPRISING A SILVER HALIDE DEVELOPING AGENT AND A SILVER HALIDE SOLVENT.

3,600,171 SULFONAMIDES IN DIFFUSION TRANSFER SYSTEMS Roger M. Cole, Rochester, N.Y., assignor to Eastman Kodak Company, Rochester, NY. No Drawing. Filed Nov. 1, 1968, Ser. No. 772,798 Int. Cl. G03c 5/54 US. Cl. 96-49 24 Claims ABSTRACT OF THE DISCLOSURE Positive images of increased maximum density in dif fusion transfer systems are produced by processing the exposed photographic element in the presence of water-soluble non-silver halide reducing sulfonamides. The sulfonamides are preferably utilized in alkaline processing compositions comprising a silver halide developing agent and a silver halide solvent.

BACKGROUND OF THE INVENTION This invention relates to photographic elements containing sulfonamides and to processes using sulfonamides in diffusion transfer systems.

In one widely used form of a diffusion transfer system for producing positive images, an exposed photographic element comprising a support and at least one silver halide emulsion layer having a latent photographic image is processed by treating the photographic element with an an alkaline solution of a silver halide developing agent and a silver halide solvent. The developing agent converts the exposed silver halide to a silver image on the emulsion layer While the silver halide solvent solubilizes substantially all of the unexposed and undeveloped silver halide from the exposed emulsion layer which then transfers by diffusion from the emulsion layer onto an imagereceiving stratum superimposed on said silver halide emulsion layer where it precipitates as silver to form a positive image.

The term positive image as used herein means a reproduced image having the same lightness and darkness relationship as the original subject as it actually exists. Whether or not a reproduced image as positive or not depends on the process by which it is made. A positiveworking process produces a reproduction in which the light and dark areas correspond directly with those of the original from which it was made. A negative-Working process produces a result in which the light and dark areas are reversed. Thus a positive image may be produced from either a positive or negative depending on the process involved.

In this invention, we are concerned with the process of forming a positive image whether or not the exposure of the light-sensitive element is made from a positive or a negative original. As will be seen in the examples below, it is sometimes desirable to form the positive image in a light-sensitive element, by exposing through a negative image.

The maximum density, D of the positive image formed in many diffusion transfer processes, however, is often quite low and has to be increased in order to produce a satisfactory image. Some control over the maximum density is obtained by balancing the developing agent concentration with the amount of fixing or stabilizing compound which is present. Further control over the United States Patent 0 maximum density and tone of the positive image has been accomplished by special toning agents and salt addenda. Unfortunately, the conditions of solubility and compatibility limit the amounts and kinds of agents which can be used for this purpose. Also, it is not uncommon to find addenda which, although improving the maximum density of the positive transfer image, adversely affect contrast and other desirable characteristics.

US. 3,305,364 issued Feb. 21, 1967, to Bard et al. discloses sulfonamides in photographic developers as buffers. However, no mention is made of diffusion transfer processes.

OBJECTS OF THE INVENTION It is an object of the invention to provide a novel photographic element comprising a sulfonamide which does not reduce silver halide in an alkaline solution.

It is also an object of the invention to increase the density of positive images of diffusion transfer processes without adversely affecting contrast and other desirable properties by conducting processing in the presence of a sulfonamide.

Yet another object of the invention is to provide a novel diffusion transfer process for producing positive images of increased maximum density by use of a processing composition containing an additive which is very soluble and can be added in large amounts without undesirable side effects.

SUMMARY OF THE INVENTION These and other objects are accomplished by processing the exposed photographic elements in the aboveidentified diffusion transfer process for producing positive images in the presence of a water-soluble, non-silver halide reducing sulfonamide. The sulfonamide is preferably utilized in the alkaline processing composition comprising silver halide developing agent and silver halide solvent, but can be utilized in either the light-sensitive element or in the image-receiving material as Well. In any case, the sulfonamide is present as an active addendum in the photographic system during processing. The sulfonamide is employed in amounts sufficiently to increase the maximum density of the positive image produced which amounts generally fall in the range of about 10 to grams per liter of alkaline processing composition.

DETAILED DESCRIPTION OF THE INVENTION The sulfonamide compounds utilized in the present inwherein R represents an alkyl group, such as methyl, ethyl, n-propyl, isobutyl, B-hydroxyethyl, etc. (e.g., an alkyl group containing from 1 to 5 carbon atoms), or an aryl group such as phenyl, 0-, m, p-carboxyphenyl, psulfophenyl, etc. (e.g., a monocyclic aryl group of the benzene series), R represents an alkylene group, such as methylene, ethylene, etc., nr and n each represents a positive integer from 1 to 2 and R represents a hydrogen atom, an alkyl group (e.g., an alkyl group as defined above for R), when n is 1, and R represents an alkyl group (e.g., an alkyl group as defined above for R) or an aryl group (e.g., an aryl group as defined above for R) when n is 2.

it no-o-s 02-min Para-carboxybenzenesulfonarnide Para-sulfo-benzenesulfonamide (6) CH SO NHNH-SO CH N-(methanesulfonamido)methanesulfonamide (7) CH SO NHC H NH-SO CH 1,2-bis(methanesulfonamide)ethane (8) CH -SO NHC H OH N- ,B-hydroxyethyl) methanesulfonamide Many of the compounds embraced by the general formula above have been previously described in the prior art. These compounds can be prepared according to the procedure described by Field et al., in J. Am. Chem. Soc., 75, 934-937 (1953). The following specific example illustrates this method:

N-ethylmethanesulfonamide, C H NHSO CH is prepared from methanesulfonylchloride and ethylamine. Add 100 g. of methanesulfonylchloride to 500 ml. of benzene in a 1-liter round-bottomed flask equipped with dropping funnel, condenser and stirrer. Cool this mixture to C. in an ice bath. Add 78 g. of ethylamine dropwise from the funnel, keeping the temperature below 10 C. After all the ethylamine has been added, allow the mixture to come to room temperature. Filter the reaction mixture to remove the precipitated ethylamine hydrochloride. Remove the benzene by evaporation on a Rinco evaporator. Distill the remaining liquid at a pressure of about 11 mm. using a water pump and a Vigreaux column. Collect the product distilling at 144-149" C. The refractive'index of this N-ethyl methanesulfonamide at 25 C. is 1.4900.

Many of the other compounds within the scope of the general formula above can be prepared according to the general procedure set forth by persons familiar with the art. Thus, N-(B-hydroxyethyl)methanesulfonamide can be prepared by substituting fl-amino ethanol in place of the ethylamine indicated in Example 1. Similarly, p-carboxybenzenesulfonamide can be prepared by reacting p-cyanobenzenesulfonylchloride with ammonia and hydrolyzing the resultant p-cyanobenzenesulfonamide. The p-cyanobenzenesulfonylchloride can be prepared by the reaction of cyanobenzene with sulfo-chloride.

Any of the conventional silver halide developing agents or combinations of these developing agents may be used in the processing compositions. These include such agents as hydroquinone and substituted hydroquinones which are substituted in the 2, 3, or 6 position carbon atoms or any combination of these with lower alkyl groups such as methyl, ethyl, propyl, butyl, etc., with lower alkoxy groups, halogen atoms such as chlorine, bromine, fluorine and other groups commonly used as substituents; resorcinol; catechol; ascorbic and isoascorbic acid, preferably in the form of its alkali metal salt; the 3-pyrazolidones such as are described in Haist et al., U.S. Pat. No. 2,875,- 048; the aminophenols such as p-aminophenol, N-methyL aminophenol, etc. Developing agents containing an amino group are usually in the form of the hydrochloride of the sulfate.

The silver halide solvent used in the alkaline processing compositions may be any of the reagents which form a soluble, dilfusible complex with silver halide as is wellknown in the art of forming silver images by transfer. Illustrative of silver halide solvents that may be used are the water-soluble thiosulfates such as sodium, potassium and ammonium thiosulfates, the alkali thiocyanates, alkali selenocyanates, etc. The preferred silver halide solvents are the thiosulfates.

Other addenda commonly employed in alkaline processing compositions for diffusion transfer processes can be included in the processing compositions of the invention. These addenda include, for instance, restrainers such as potassium bromide, stain preventives such as alkali metal sulfites, sequestering agents such as ethylenediamine tetracetic acid, 1,3-dian1ino-2-propanol tetracetic acid, tetrasodium salt, etc.

As aforementioned, the processing compositions used to initiate development of the exposed light-sensitive elements in the diffusion transfer process of the invention are strongly alkaline generally having a pH of at least 9. Alkali metal hydroxides such as sodium hydroxide and potassium hydroxide and sodium carbonate, or mixtures thereof, are advantageously used in the compositions for imparting the alkalinity. The processing compositions are generally aqueous liquids or solutions which may be used in a web-type process by imbibing a hydrophilic web of the type described in Tregillus et al., U.S. Pat. No. 3,179,517 or in a viscous solution of the type used in rupturable pods for in-camera processing such as described in U.S. Pat. 2,435,717. When used in pod processing, the processing compositions generally contain thickening agents such as hydroxyethyl cellulose or carboxymethyl cellulose. Thickened processing compositions typically have viscosities of at least 5,000 cps. to 100,000 or even 200,000 cps.

The silver halide emulsions utilized in preparing photographic or light-sensitive elements used in the present diffusion transfer systems can be any of the conventional negative-type, developing-out emulsions. When the sulfonamide is incorporated in the emulsion, it can be incorporated in an amount suflicient to provide about 10 to about 500 mg./ft. of sulfonamide. Typical suitable silver halides include silver chloride, silver bromide, silver bromoiodide, silver chloroiodide, silver chlorobromoiodide and the like. Mixtures of more than one of such silver halides can also be utilized. In accordance with usual practice, such silver halide emulsions can contain spectral sensitizers, speed-increasing addenda, hardeners, coating aids, plasticizers, antifoggants and the like conventional emulsions addenda.

In preparing such silver halide emulsions, as well as in preparing the various layers of photographic elements used in the present diffusion transfer process, including the layers containing dye developers and colorless hydroquinone derivatives, mordant-containing reception layers, interlayers, topcoat layers and the like, a wide variety of hydrophilic organic colloids can be utilized as the vehicle or carrier. Gelatin is preferably used as the hydrophilic colloidal or carrier material although such materials as polyvinyl alcohol and its water-soluble derivatives and copolymers, water-soluble copolymers such as polyacrylamide, imidized polyacrylamide, etc., and other watersoluble film-forming materials that form water-peremeable coats such as colloidal albumin, water-soluble cellulose derivatives, etc., can be utilized in preparing the photographic elements. Compatible mixtures of two or more of such colloids can also be utilized.

The silver halide emulsion layers used in the preparation of the diffusion transfer element can be coated on a variety of supports. Typical supports include cellulose nitrate film, cellulose acetate film, polyvinyl acetal film, polystyrene film, polyethylene terephthalate film, polyethylene film, polypropylene film, paper, polyethyleneclcgated paper, polypropylene-coated paper, glass and the li e.

Similarly, a wide variety of receiving sheets can be utilized to receive the transfer images from the photographic elements. When the sulfonamide is coated on the receiving sheet, it can have a range of from about to about 500 mg./ft. Typical reception layers for receiving sheets include such materials as linear polyamides, proteins such as gelatin, polyvinyl pyrrolidones, poly-4-vinyl pyridine, polyvinyl alcohol, polyvinyl salicylal, partially hydrolyzed polyvinyl acetate, methyl cellulose, regenerated cellulose, or mixtures of such. These reception layers can be coated on a suitable support of the type described above for the light-sensitive element of the invention and including transparent as well as opaque supports. Also, receiving sheets that release acidic material such as that derived from an acidic polymer or other acidic compounds at a controlled rate as are described in US. Pat. 2,584,030 are particularly useful. Such acidic materials are typically positioned in layers on the receiving sheet below the dye developer reception layer, there suitably being a spacer layer between the acid layer and the mordanting layer to control the release of acidic material. Such acidic materials serve to neutralize residual portions of the alkaline activator on the receiving sheet. It is preferred to provide precipitation nuclei, e.g., metallic sulfides such as, for example, lead sulfide, cadmium sulfide, zinc sulfide and nickel sulfide, and metallicselenides such as lead selenide, and zinc selenide, in the imagereceiving layer to facilitate the formation of the silver image thereon. Such precipitating nuclei may also be dispersed directly in the processing solution, as disclosed in US. Pat. 2,622,822.

In those cases where the diffusion transfer process involves the development of dye images by means of developing agents such as the paraphenylenediamine type developing agents, suitable colored or colorless coupler compounds of the phenolic, hydroxyl, pyrazolone and open chain reactive methylene types may be employed in the emulsion, receiving sheet or processing solutions. The sulfonamides are similarly beneficial for use with other types of diffusion transfer processes, such as those wherein a unitary element is provided" having, for example, a removable cellulose ether phthalate silver halide emulsion layer coated upon a receiving layer containing a silver precipitant. The element is exposed in a suitable manner, development initiated in the presence of a silver halide solvent and the sulfonamide, and a positive image formed in the receiving layer accompanied by removal of the overlying emulsion layer containing the negative image.

The improvement in the maximum density of positive images can be obtained' in diflusion transfer systems wherein the initial density is low, that is, below about 1.9. Little or no improvement is usually found where the initial density is 1.9 or higher. The density increases with various speed ranges of light-sensitive photographic films, from low speed, high definition films to very high speed, coarser grain films.

The following examples are included for a further understanding of the invention:

EXAMPLE 1 Diffusion transfer system using a 4,4-dimethyl-1- phenyl-3-pyrazolidone Strips of a high speed silver bromoiodide emulsion are given sensitometric exposures and processed by diffusion transfer. The receiver is a sheet of reflection print paper coated with a gelatin layer containing nickel sulfide nuclei. The processing solution consists of:

Water---750.0 ml.

Potassium sulfite12.0 g.

Potassium carbonate40.0 g. 4,4-dimethyl-1-phenyl-3-pyrazolidone1.2 g. Potassium hydroxide, 45 in water10.0 ml. Sodium isoascorbate-40.0 g.

Sodium thiosulfate, crystalline-20.0 g.

Potassium iodide, 0.1% in water50.0 ml.

Potassium bromide-2.0 g.

Waterto 1000.0 ml.

Tridecoxyhexaethoxy sulfuric acid, ammonium salt, 2.0% in water3 0.0 ml.

The control negatives are soaked in the processing solution for 4 seconds at 78 F. and immediately squeeged into contact with the receiving sheet. After 2 minutes they are separated and rinsed in water and dried. The maximum density of the positive sensitometric curve is 1.28.

A portion of the solution above is modified by the addition of 40 grams per liter of methanesulfonamide. Sensitometric strips are immersed in the solution and processed as above. The maximum densities produced in the positive image is 1.68. A density increase of 0.40 results from the use of the methane sulfonamide. The speed and fog levels remain unchanged from the controls.

EXAMPLE 2 Use in a silver-dye light sensitive element The receiver sheet, sensitive to light, is made by coating a cellulose acetate support with a 0.004-inch wet thickness layer of a 5% gelatin solution containing silver nitrate and a sensitizing dye, 3-carboxymethyl-5-[(3-methyl-2- thiazolinylidene)ethylidene]rhodanine. The receiver sheet is used as a printing paper for making a positive print by exposing in a contact printer to a negative subject. A fine grain, low speed silver chlorobromide emulsion is used as the source of silver for physical development. After exposure, the receiver layer is squeeged into contact with the photographic film (unexposed) which is dipped for 4 seconds into the following solution:

Water750.() ml.

Sodium sulfite10.0 g.

Sodium carbonate monohydrate35.0 g.

Potassium hydroxide, 45 in water-5 .0 ml.

4,4-dimethyl-1-phenyl-3-pyrazolidone1.0 g.

Sodium isoascorbate40.0 g.

Sodium thiosulfate, crystalline17.0 g.

Potassium iodide, 0.1% in water-50.0 ml.

Potassium bromide3.0 g.

Water-to 1000.0 ml.

Tridecoxyhexaethoxy sulfuric acid, ammonium salt, 2%

in water-30.0 ml.

The strips remain in contact for 2 minutes, then are separated, and the receiver sheet is rinsed briefly in water and dried. The photographic film is discarded. The maximum density of the positive image in the receiver sheet is 1.20.

When 40 grams per liter of methanesulfonamide are added to the processing solution and the experiment repeated using the modified solution, the maximum density of the positive image in the receiver sheet is 1.56.

EXAMPLE 3 Diffusion transfer system using methyl-p-aminophenol sulfate hydroquinone-isoascorbate developer A developer having the following composition is used:

Water-750.0 cc.

Sodium sulfite-l0.0 g. Methyl-p-aminophenol sulfate-6.0 g. Sodium carbonate, monohydrate35.0 g. Potassium hydroxide, 45% in water-13.0 cc. Sodium isoascorbate40.0 g.

Sodium thiosulfate, crystalline12.0 g. Hydroquinone-2.0= g.

Potassium bromide-2.0 g.

Potassium iodide-50.0 mg. Methanesulfonamide'40.0 g.

Water--to 1.0 liter Tridecoxyhexaethoxy sulfuric acid, ammonium salt, 2%

in water-30.0 cc.

Processing is carried out as in Example 1. Without added methanesulfonamide, the maximum density produced as in Example 1, is 1.30. The presence of 50 grams per liter of methanesulfonamide causes the maximum density to increase to 1.70.

This invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention as described hereinabove and as set forth in the appended claims.

I claim:

1. An aqueous photographic developer composition for diffusion transfer systems comprising photographic silver halide developing agent, silver halide solvent and a watersoluble, non-silver halide reducing sulfonamide.

2. The composition of claim. 1 wherein the sulfonamide has the general formula:

wherein m and 21 each represents a positive integer of from 1 to 2, R represents an alkylene group, R represents a member selected from the class consisting of an alkyl group and an aryl group, and R when n is 1, represents a member selected from the class consisting of a hydrogen atom, an alkyl group and an aryl group, and R when n is 2, represents a member selected from the class consisting of an alkyl group and an aryl group.

3. The composition of claim 1 wherein the sulfonamide has the general formula:

wherein R represents an alkyl group, and R represents a member selected from the class consisting of a hydrogen atom and an alkyl group.

4. The composition of claim 1 wherein the sulfonamide is methanesulfonamide.

5. The composition of claim 1 wherein the sulfonamide is dimethanesulfonamide.

6. The composition of claim 1 wherein the sulfonamide is N-ethylmethanesulfonamide.

7. The composition of claim 1 wherein the sulfonamide is diethanesulfonamide.

8. The composition of claim 1 wherein the silver halide developing agent is 4,4-dimethyl-l-phenyl-3-pyrazolidone.

9. The composition of claim 1 wherein the silver halide developing agent is alkali metal isoascorbate.

10. An aqueous alkaline photographic developer composition comprising water and alkaline material, a silver halide developing agent, silver halide solvent, and a watersoluble, non-silver halide reducing sulfonamide.

11. The composition of claim 1 wherein the sulfonamide is present in an amount of about 10 to 100 grams per liter of said solution.

12. A photographic element comprising a support having thereon a silver precipitating agent and a substantially dried layer comprising a water-soluble, non-silver halide reducing sulfonamide in an amount of from about 10 to about 500 mg./ft.

13. The element of claim 12 wherein the sulfonamide has the general formula:

wherein m and it each represents a positive integer of from 1 to 2, R represents an alkylene group, R represents a member selected from the class consisting of an alkyl group and an aryl group, and R when n is 1, represents a member selected from the class consisting of a hydrogen 8 atom, an alkyl group and an aryl group, and R when n is 2, represents a member selected from the class consisting of an alkyl group and an aryl group.

14. The element of claim 12 wherein the sulfonamide has the general formula:

wherein R represents an alkyl group, and R represents a member selected from the class consisting of a hydrogen atom and an alkyl group.

15. The element of claim 12 wherein the support has thereon a light-sensitive silver halide emulsion.

16. The element of claim 12 wherein the support has thereon a silver precipitating agent.

17. A process of physically developing an exposed photographic element comprising a,support and a lightsensitive silver salt or complex layer containing a latent photographic image with a silver halide developing agent and a soluble silver compound in the presence of a watersoluble, non-silver reducing sulfonamide 18. The process of claim 17 wherein the sulfonamide has the general formula:

wherein m and it each represents a positive integer of from 1 to 2, R represents an alkylene group, R represents a member selected from the class consisting of an alkyl group and an aryl group, and R when n is 1, represents a member selected from the class consisting of a hydrogen atom, an alkyl group and an aryl group, and R when n is 2, represents a member selected from the class consisting of an alkyl group and an aryl group.

19. The process of claim 17 wherein the sulfonamide has the general formula:

wherein R represents an alkyl group, and R represents a member selected from the class consisting of a hydrogen atom and an alkyl group.

20. The process of claim claim 17 wherein the sulfonamide is methanesulfonamide.

21. The process of claim 18 wherein the sulfonamide is dimethanesulfonarnide.

22. The process of claim 17 wherein the sulfonamide is N-ethylmethanesulfonamide.

23. The process of claim 17 wherein the sulfonamide is diethanesulfonamide.

24. In the processing of an exposed photographic element comprising a support and a silver halide emulsion layer containing a latent photographic image, said processing being effected by developing said exposed silver halide layer with a silver halide developing agent and a silver halide solvent and transferring undeveloped silver to an image-receiving material superimposed on said silver halide emulsion and thereby forming a positive transfer image, the improvement which comprises effecting said processing in the presence of a water-soluble, non-silver reducing sulfonamide.

References Cited UNITED STATES PATENTS 3,305,364 2/1967 Bard et al. 9666 3,371,060 2/1968 Taylor 9629 3,438,776 4/1969 Yudelson 9629 WILLIAM D. MARTIN, Primary Examiner R. M. SPEER, Assistant Examiner US. Cl. X.R. 9676 

